The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
Engine brake torque is determined in various manners. Typically, an estimate of engine brake torque is created by collecting a large matrix of steady state engine operating points and regressing the measured engine brake torque against available engine operating variables, such as engine speed, mass airflow, spark and the like. Typically, the engine brake torque estimate is good to within plus or minus 15 Newton meters or about 10 percent. A more accurate determination of torque may allow a more precise control of the engine. More precise control of the engine may lead to increased power and increased fuel economy.